PSA: MPC-HC's overlay renderer works with DXVA2 (copy-back)

While I've known for a while that MPC-HC's overlay renderer does not work with DXVA2 (native) as is noted by the MPC-HC GUI itself, I only just discovered by pure accident today that its overlay renderer does work with DXVA2 (copy-back)!

This can be extremely useful on very low-end CPUs (like my laptop's AMD E-350) where every ounce of CPU performance counts since, not only does overlay itself have less CPU utilization compared to EVR-CP, but overlay's scaling algorithm looks better than bilinear as well while still having similar performance to it (it isn't quite to the level of bicubic, but that has greater CPU utilization anyway); overlay also looks a bit better than my display's/GPU's built in scaling algorithm (like if I set my desktop resolution to 1280x720 for a 720p video and my display/GPU scales that up to my screen's native resolution).

Just keep in mind that the scaling algorithm for the overlay renderer only seems to work properly (otherwise you get nearest neighbor scaling) when Aero and/or desktop composition is disabled - this seems to occur automatically on at least older Intel GPUs (like the 965GMA), but I had to manually disable Aero for my E-350's integrated Radeon graphics.